Active matrix organic light-emitting diode (AMOLED) display panels have been presented that have in-cell touch sensors, where the cathode of the organic light-emitting diode (OLED) is divided into a plurality of separate electrode areas, each serving as a touch sensor to which a touch scan signal is applied during a touch sense phase.
Due to its working principle, such an in-cell touch sensor has a strict requirement for the cathode-to-ground capacitance (self-capacitance) of the OLED. I.e., influence of potential additional capacitance (e.g., capacitance between the anode and cathode of the OLED) on the self-capacitance should be avoided at the largest extent in an AMOLED pixel circuit to ensure a good accuracy for touch sensing. Currently, there is no satisfactory solution that can meet such a requirement.
Thus, there is a need for an improved working mechanism for the AMOLED pixel circuit having in-cell touch sensors.